// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_
#define CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_

#include "base/callback_forward.h"

#include "content/common/content_export.h"

namespace content {

// The BrowserAccessibilityState class is used to determine if the browser
// should be customized for users with assistive technology, such as screen
// readers.
class CONTENT_EXPORT BrowserAccessibilityState {
public:
    virtual ~BrowserAccessibilityState() { }

    // Returns the singleton instance.
    static BrowserAccessibilityState* GetInstance();

    // Enables accessibility for all running tabs.
    virtual void EnableAccessibility() = 0;

    // Disables accessibility for all running tabs. (Only if accessibility is not
    // required by a command line flag or by a platform requirement.)
    virtual void DisableAccessibility() = 0;

    // Resets accessibility to the platform default for all running tabs.
    // This is probably off, but may be on, if --force_renderer_accessibility is
    // passed, or EditableTextOnly if this is Win7.
    virtual void ResetAccessibilityMode() = 0;

    // Called when screen reader client is detected.
    virtual void OnScreenReaderDetected() = 0;

    // Returns true if the browser should be customized for accessibility.
    virtual bool IsAccessibleBrowser() = 0;

    // Add a callback method that will be called once, a small while after the
    // browser starts up, when accessibility state histograms are updated.
    // Use this to register a method to update additional accessibility
    // histograms.
    virtual void AddHistogramCallback(base::Closure callback) = 0;

    virtual void UpdateHistogramsForTesting() = 0;
};

} // namespace content

#endif // CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_
